WO2008024061A1 - A method of removing unwanted sulphur compounds from the insulating oil of an electrical apparatus - Google Patents
A method of removing unwanted sulphur compounds from the insulating oil of an electrical apparatus Download PDFInfo
- Publication number
- WO2008024061A1 WO2008024061A1 PCT/SE2007/050548 SE2007050548W WO2008024061A1 WO 2008024061 A1 WO2008024061 A1 WO 2008024061A1 SE 2007050548 W SE2007050548 W SE 2007050548W WO 2008024061 A1 WO2008024061 A1 WO 2008024061A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- electrical apparatus
- iodine
- insulating oil
- electrically insulating
- added
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 38
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical class [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title description 6
- 150000002497 iodine compounds Chemical class 0.000 claims abstract description 37
- BWFPGXWASODCHM-UHFFFAOYSA-N copper monosulfide Chemical compound [Cu]=S BWFPGXWASODCHM-UHFFFAOYSA-N 0.000 claims abstract description 33
- 239000000463 material Substances 0.000 claims abstract description 30
- 238000006467 substitution reaction Methods 0.000 claims abstract description 8
- 239000003795 chemical substances by application Substances 0.000 claims description 29
- 239000011630 iodine Substances 0.000 claims description 25
- 229910052740 iodine Inorganic materials 0.000 claims description 25
- PNDPGZBMCMUPRI-UHFFFAOYSA-N iodine Chemical compound II PNDPGZBMCMUPRI-UHFFFAOYSA-N 0.000 claims description 15
- 238000003860 storage Methods 0.000 claims description 12
- 239000007800 oxidant agent Substances 0.000 claims description 11
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 claims description 6
- 239000011550 stock solution Substances 0.000 claims description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 229910052760 oxygen Inorganic materials 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 5
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims description 4
- 150000001351 alkyl iodides Chemical class 0.000 claims description 4
- -1 amine compound Chemical class 0.000 claims description 4
- 150000001875 compounds Chemical class 0.000 claims description 4
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 claims description 3
- 150000004965 peroxy acids Chemical class 0.000 claims description 3
- 239000007795 chemical reaction product Substances 0.000 claims 2
- 229910000043 hydrogen iodide Inorganic materials 0.000 claims 2
- 229920000180 alkyd Polymers 0.000 claims 1
- 230000001590 oxidative effect Effects 0.000 claims 1
- 239000003921 oil Substances 0.000 description 62
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 19
- 238000006243 chemical reaction Methods 0.000 description 12
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 239000004020 conductor Substances 0.000 description 7
- 238000002955 isolation Methods 0.000 description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 5
- 229910052802 copper Inorganic materials 0.000 description 5
- 239000010949 copper Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000010292 electrical insulation Methods 0.000 description 4
- 238000009413 insulation Methods 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 239000013043 chemical agent Substances 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 239000005749 Copper compound Substances 0.000 description 2
- 239000005864 Sulphur Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004320 controlled atmosphere Methods 0.000 description 2
- 150000001880 copper compounds Chemical class 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000000593 degrading effect Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 150000003464 sulfur compounds Chemical class 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 229940126540 compound 41 Drugs 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 150000002366 halogen compounds Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 150000007524 organic acids Chemical group 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000002000 scavenging effect Effects 0.000 description 1
- 239000002594 sorbent Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/08—Cooling; Ventilating
- H01F27/10—Liquid cooling
- H01F27/12—Oil cooling
- H01F27/14—Expansion chambers; Oil conservators; Gas cushions; Arrangements for purifying, drying, or filling
Definitions
- the present invention relates to a method of treating copper sulphide deposits present in electrically insulating layers in an electrical apparatus.
- Insulating oils are used in a number of different apparatus in the field of electrical power transmission and electrical power generation, for example; power transformers, distribution transformers, tap changers, switchgear and reactors .
- electrically insulating oils often contain traces of reactive sulphur compounds, which may react with copper, forming copper sulphide (CU2S) .
- Copper sulphide is insoluble in oil and may form deposits on surfaces and materials in contact with the electrically insulating oils inside the electrical apparatus.
- the copper sulphide is a semiconductor and the formation of a semi-conducting deposit on surfaces and materials in the electrical apparatus may degrade or disrupt the operation of the apparatus.
- the isolation material usually cellulose material e.g. paper
- Semi-conducting copper sulphide deposits on surfaces of solid isolation materials (such as wood, ceramic, and pressboard) inside the electrical apparatus may also create similar problems.
- WO2005115082 entitled “Method for removing reactive sulfur from insulating oil” describes a method for removing sulphur- containing compounds from insulating oil by exposing the oil to at least one sulphur scavenging material and exposing the oil to at least one polar sorbent.
- JP2001311083 describes how sulfur compounds in electrically isolation oils can be removed before the use in an electrical apparatus by storing the oil in a vessel containing copper or copper alloys. The sulfur compounds in the oil react with the copper and are thus captured and removed from the oil prior to the use in the electrical apparatus.
- One embodiment of the present invention is to provide a method by means of which semi-conducting copper sulphide deposits on materials and surfaces inside an electrical apparatus are treated with a halogen compound in oil.
- An object of a preferred embodiment of the present invention is to provide a method by means of which copper sulphide deposits on materials and surfaces inside an electrical apparatus are treated.
- One or more objects of the invention is achieved by means of the initially defined method, characterized in that a iodine compound causing a reaction of said copper sulphide deposits on materials and surfaces inside an electrical apparatus.
- the copper sulphide is a semiconductor and the formation of a semi-conducting deposit on the isolation material might lead to a degrading of the insulation properties of the insulating material and oil system which could lead to short circuits in the electrical apparatus. These short circuits can be avoided by removing the copper sulphide from the isolation material or transforming the copper sulphide to compounds with lower conductivity.
- said iodine compound comprises iodine in elementary form ( ⁇ 2), according to another embodiment said iodine compound comprises hydrogen iodide (HI) and according to another embodiment said iodine compound comprises alkyl iodide (R-I) .
- iodine compound is added to the electrical insulation oil.
- the iodine is added to the remaining electrically insulating oil in the electrical apparatus as a stock solution.
- the iodine is added by dissolving iodine crystals in the electrically insulating oil in the electrical apparatus.
- the iodine is added by dissolving iodine crystals in the electrically insulating oil outside of the electrical apparatus.
- the materials that are to be treated inside the electrical apparatus comprise any from the group of: paper, pressboard, wood and other solid/fibrous insulating materials in contact with the electrically insulating oil
- the surfaces that are to be treated inside the electrical comprise any from the group of: insulated conductors, exposed conductors, magnetic core and other solid surfaces in contact with the electrically insulating oil.
- a method is provided that further comprising the step of the iodine is added in the form of iodine vapor.
- a method is provided that a substantial amount of an electrically insulating oil, normally present in said electrical apparatus, is removed and said iodine is added in the form of iodine vapor .
- a method is provided that further comprising the step of the treatment with the chemical agent is performed in a controlled atmosphere.
- the atmosphere is controlled by controlling parameters such as; humidity, temperature, ozone content, nitrogen and oxygen content.
- a method is provided that further comprising the step of heating the conductors in the electrical apparatus by a current flowing through the conductors during treatment.
- a method is provided that further comprising the step of subsequent to the treatment with iodine compound, a second treatment with an oxidizing agent is performed.
- the oxidizing agent comprises ozone (O3)
- the oxidizing agent comprises chlordioxide (CIO2)
- the oxidizing agent comprises peroxy acid (R-O3H) .
- a method is provided that further comprising the step of subsequent to the treatment with iodine compound, a second treatment with a complex building agent is performed.
- the complex building agent comprises an organic dibasic amine compound (H 2 N-R-NH 2 ) .
- the oxidizing agent in the second treatment comprises of a mix of oxygen and nitrogen which is added to the controlled atmosphere.
- a copper compound formed as a result of the copper sulphide being treated with said agent, is let to remain on the transformer windings, and that the transformer is re-filled with transformer oil.
- Figure 1 is a flowchart of one embodiment of the invention.
- Figure 2 is a flowchart of another embodiment of the invention .
- Figure 3 illustrates a schematic process diagram of one method of the invention.
- Figure 4 illustrates a schematic process diagram of one method of the invention.
- Figure 5 is a schematic system view of one embodiment of the present invention.
- Figure 6 is a schematic system view of another embodiment of the present invention.
- Figure 1 shows a schematic process diagram of the method.
- the electrical apparatus and the electrically insulating oil is prepared for the treatment.
- the iodine compound in block 31 is fed into the electrical apparatus and mixed with electrically insulating oil inside the apparatus.
- the substitution reaction (treatment) of the copper sulphide on materials and surfaces inside the electrical apparatus occurs.
- the reaction transforms the semi conducting copper sulphide on materials and surfaces inside the electrical apparatus to mainly non-conducting copper compounds.
- the excess or un-reacted iodine compound is removed.
- Figure 2 shows a schematic process diagram of one method.
- the electrical apparatus is taken offline.
- the temperature of the oil in the electrical apparatus is adjusted to the optimal temperature for the reaction to occur.
- From the iodine compound storage (which can be iodine ( ⁇ 2), hydrogen iodide (HI), alkyl iodide (R-I)) in block 6.
- the iodine compound is added to the electrically insulating oil in the electrical apparatus and the reaction occurs inside the electrical apparatus in block 4. Excess iodine compound leaving the electrical apparatus during reaction is taken care of in block 7.
- Block 5 is the optional second treatment step which can be a treatment with an oxidizing agent such as ozone, chlordioxide or a peroxy acid.
- the optional second treatment step in block 5 can also be a reaction between the treated copper sulphide and a complex building agent such as an organic dibasic amine compound, with the general chemical formula H 2 N-R-NH 2 , or an organic compound with at least two organic acid functional groups, with the general chemical formula HOOC-R-COOH.
- a complex building agent such as an organic dibasic amine compound, with the general chemical formula H 2 N-R-NH 2 , or an organic compound with at least two organic acid functional groups, with the general chemical formula HOOC-R-COOH.
- Figure 3 illustrates a flowchart of one embodiment of the invention.
- the electrically insulating oil remains inside the electrical apparatus 20 and the treatment can start.
- An iodine compound storage means 21 supplies the iodine compound for the reaction to occur.
- the iodine compound is fed 25 into the circulation cycle 28 of the atmosphere in the electrical apparatus 20 and the atmosphere in the apparatus is controlled (with respect to parameters such as; humidity, temperature, nitrogen and oxygen content) .
- the atmosphere with iodine vapor inside the electrical apparatus 20 that is to be treated has to be well mixed. This mixing assists the diffusion of the iodine onto materials and surfaces inside the electrical apparatus to ensure that the reaction rate is sufficient.
- one possibility of mixing the atmosphere is shown as a circulation cycle 28 with a pump 23. Un-reacted iodine and excess atmosphere is removed 26 and fed into a cold trap 22 that removes the iodine vapor. The stream leaving the cold trap 22 contains only the excess atmosphere 27.
- Figure 4 illustrates a flowchart of one embodiment of the invention. In this flowchart a substantial amount of the oil remains in the electrical apparatus 10 and the treatment can start.
- An iodine compound stock solution 11 is used to add the required iodine compound for the reaction to occur.
- the iodine compound stock solution is fed 15 into the electrical apparatus 10 where it mixes with the remaining oil.
- the atmosphere over the electrically insulating oil is controlled (with respect to parameters such as; humidity, temperature, nitrogen and oxygen content) .
- the electrically insulating oil and the stock solution of iodine in the electrical apparatus 10 have to be mixed to assist the diffusion of the iodine onto materials and surfaces inside the electrical apparatus to ensure that the reaction rate is sufficient.
- an internal mixer 14 inside the electrical apparatus 10.
- Un-reacted iodine compound evaporates and excess atmosphere is removed 16 and fed into a treatment unit e.g. a cold trap 12 that removes the iodine compound vapor.
- the stream leaving the cold trap 12 contains only the excess atmosphere 17.
- Another way of adding the iodine to the electrically insulating oil is by adding iodine crystals directly to the oil. Yet another way would be to pump the oil in a circulation cycle 28 (fig 3) and pass the oil through a bed of iodine crystals and feeding the iodine rich oil back into the apparatus.
- FIG. 5 is a schematic system view of one embodiment of the present invention.
- the electrical apparatus 40 is filled with electrically insulating oil for electrical protection and heat transfer. From different sources 41, 45 chemical agents are added to the insulating oil.
- the chemical agents can be in the form of concentrated agent or in the form of agents dissolved in electrical insulation oil.
- the iodine compound is added to the oil.
- Some oil have to be removed, by a dump line 43 to a storage vessel 44, before the agent, in the form of agents dissolved in electrical insulation oil is added to the electrical apparatus 40, to prevent overflow.
- the agent is also fed into the electrical apparatus 40 which is filled with electrically insulating oil.
- the adding of complex building agent can be performed after the substitution agent (iodine compound) have been added and reacted with copper sulphide on materials and surfaces inside the electrical apparatus.
- the adding of complex building agent can be performed at the same time as the substitution agent is added.
- the complex building agent is added in the form of agent dissolved in electrically insulating oil. Some oil have to be removed, by a dump line 43 to a storage vessel 44, before the complex building agent, in the form of agents dissolved in electrical insulation oil is added to the electrical apparatus 40, to prevent overflow.
- Figure 6 is a schematic system view of another embodiment of the present invention.
- Part of the electrically insulating oil is drawn 53 from the electrical apparatus 50 into a storage vessel 51.
- the agent is added to the extracted oil in concentrated form e.g. in liquid form or as crystals.
- the oil with right amount of agent is fed back 52 into the electrical apparatus 50.
- the substitution agent is iodine and then the iodine is added to the storage vessel 51 as iodine crystals that slowly dissolves in the electrically insulating oil.
- the oil in the storage vessel 51 can be stirred or agitated and/or heated to speed up the dissolving of iodine crystals.
- the complex building agent can be added to drawn out oil in the form of crystals or stock solution.
- the oil in the storage vessel 51 is then stirred or agitated and/or heated to generate a uniform agent solution and then fed back into the electrical apparatus 50.
- One embodiment of the present invention teaches that the iodine compound is added first and then allowed to react with copper sulphide on materials and surfaces inside the electrical apparatus for some time. When the reaction between the iodine compound and copper sulphide on materials and surfaces in the electrical apparatus 50 is finished, the complex building agent is added to the oil which is fed into the electrical apparatus 50.
- Another embodiment of the present invention teaches that the iodine compound is added first and then allowed to react with copper sulphide on materials and surfaces inside the electrical apparatus for some time. When the reaction between the iodine compound and copper sulphide on materials and surfaces in the electrical apparatus 50 is finished, an oxidizing agent is added to the oil which is fed into the electrical apparatus 50.
- Another embodiment of the present invention teaches that the iodine compound and the complex building agent are added to the oil in the storage vessel 51 at the same time and then fed into the electrical apparatus 50.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Transformer Cooling (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
- Organic Insulating Materials (AREA)
- Fats And Perfumes (AREA)
- Fire-Extinguishing Compositions (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BRPI0715744-4A BRPI0715744A2 (en) | 2006-08-25 | 2007-08-13 | Method of removing unwanted sulfur compounds from the insulating oil of an electrical equipment |
EP07794158A EP2064714A1 (en) | 2006-08-25 | 2007-08-13 | A method of removing unwanted sulphur compounds from the insulating oil of an electrical apparatus |
US12/438,768 US20090324808A1 (en) | 2006-08-25 | 2007-08-13 | Method of removing unwanted sulphur compounds from the insulating oil of an electrical apparatus |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE0601744-6 | 2006-08-25 | ||
SE0601744A SE0601744L (en) | 2006-08-25 | 2006-08-25 | Procedure for the treatment of an electrical appliance |
SE0701284-2 | 2007-05-28 | ||
SE0701284 | 2007-05-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2008024061A1 true WO2008024061A1 (en) | 2008-02-28 |
Family
ID=39107061
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SE2007/050548 WO2008024061A1 (en) | 2006-08-25 | 2007-08-13 | A method of removing unwanted sulphur compounds from the insulating oil of an electrical apparatus |
Country Status (6)
Country | Link |
---|---|
US (1) | US20090324808A1 (en) |
EP (1) | EP2064714A1 (en) |
AR (1) | AR062531A1 (en) |
BR (1) | BRPI0715744A2 (en) |
RU (1) | RU2413324C2 (en) |
WO (1) | WO2008024061A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2333043A1 (en) * | 2009-12-07 | 2011-06-15 | ABB Research Ltd. | Method for removing copper sulphide (cu2s) deposited onto cellulose-based material in transformer |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1876221A1 (en) * | 2006-07-07 | 2008-01-09 | Abb Research Ltd. | A method of treating an electrically insulating oil |
JP5234440B2 (en) * | 2010-02-17 | 2013-07-10 | 三菱電機株式会社 | Oil-filled electrical equipment life diagnosis device, oil-filled electrical equipment life diagnosis method, oil-filled electrical equipment deterioration suppression device, and oil-filled electrical equipment deterioration control method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB277328A (en) * | 1926-09-10 | 1928-05-31 | Siemens Ag | Improvements in or relating to electric switches |
JPS5589381A (en) * | 1978-12-27 | 1980-07-05 | Dainippon Toryo Co Ltd | Treatment of fluorescent substance emitting light in electric field |
JPS64613A (en) * | 1987-06-23 | 1989-01-05 | Mitsubishi Rayon Co Ltd | Manufacture of conductive high polymer material |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3663742A (en) * | 1969-10-06 | 1972-05-16 | Furukawa Electric Co Ltd | Method of mitigating sulfide trees in polyolefin insulated conductors |
-
2007
- 2007-08-13 EP EP07794158A patent/EP2064714A1/en not_active Withdrawn
- 2007-08-13 US US12/438,768 patent/US20090324808A1/en not_active Abandoned
- 2007-08-13 WO PCT/SE2007/050548 patent/WO2008024061A1/en active Application Filing
- 2007-08-13 RU RU2009109842/07A patent/RU2413324C2/en not_active IP Right Cessation
- 2007-08-13 BR BRPI0715744-4A patent/BRPI0715744A2/en not_active IP Right Cessation
- 2007-08-24 AR ARP070103780A patent/AR062531A1/en unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB277328A (en) * | 1926-09-10 | 1928-05-31 | Siemens Ag | Improvements in or relating to electric switches |
JPS5589381A (en) * | 1978-12-27 | 1980-07-05 | Dainippon Toryo Co Ltd | Treatment of fluorescent substance emitting light in electric field |
JPS64613A (en) * | 1987-06-23 | 1989-01-05 | Mitsubishi Rayon Co Ltd | Manufacture of conductive high polymer material |
Non-Patent Citations (2)
Title |
---|
PATENT ABSTRACTS OF JAPAN * |
YU J.-H. ET AL.: "Hydrothermal Syntheses, Supramolecular Structures and the Third-order Non-linear Optical Properties of Three Copper(I) Halide Amine Complexes Connected via Secondary Bonding Interactions", CHINESE JOURNAL OF CHEMISTRY, vol. 20, 2002, pages 851 - 857, XP003018688 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2333043A1 (en) * | 2009-12-07 | 2011-06-15 | ABB Research Ltd. | Method for removing copper sulphide (cu2s) deposited onto cellulose-based material in transformer |
WO2011069757A1 (en) * | 2009-12-07 | 2011-06-16 | Abb Research Ltd | Method for removing copper sulphide (cu2s) deposited onto cellulose-based material in transformer |
Also Published As
Publication number | Publication date |
---|---|
RU2009109842A (en) | 2010-09-27 |
AR062531A1 (en) | 2008-11-12 |
RU2413324C2 (en) | 2011-02-27 |
BRPI0715744A2 (en) | 2013-07-16 |
EP2064714A1 (en) | 2009-06-03 |
US20090324808A1 (en) | 2009-12-31 |
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